Highway marker



April 7, 1936. D TAYLOR 2,036,373

HIGHWAY MARKER Filed April 29, 1955 Swan MM 7 i af a 7 .5071 0 00!; Z).Way 3 Patented Apr. 7, 1936 PATENT OFFICE errant HIGHWAY MARKER,

Donald D. Taylor, Duncannon, Pa assignor to Advance EngineeringCorporation, huncannou, Pa, a corporation oi PennsylvaniaApplicationdnril ea recs, Serial No. irate lit tllaims.

My invention relates to the marking of streets and highways with surfaceindicia for defining tramc lanes, pedestrian crossings and'the like.

l-leretoiore, several expedients have been attempted for the generalpurposes with which the present invention is concerned. @ne of the firstto be used and that which, to the present time, is most generallyemployed, consists in the painting of appropriate lines upon the road orstreet surface. Such lines have the great disadvantage of short life,due to the abrasive action of vehicle wheels rolling and draggingthereon, weathering, and to staining and obliteration by road tar andspent oil dropping from the engines and other lubricated parts ofautomobiles.

Because of this primary objectionto the painted line as a highwaymarker, numerous devices have been ofiered as substitutes, such devices,for the most part, being in the nature of studs provided with pin-likesecuring portions which are driven or otherwise anchored in the body ofthe highway at appropriately'spaced positions to give the appearance ofa dotted or broken line. Such devices are expensive for the purpose,partially :3 because, to remain lustrous, they must be fabricated of, orjacketed with, expensive corrosionresisting metal such as Monel orstainless steel. In some instances, attempts have been made to jewel theexposed portions of otherwise nonlustrous studs with faceted pieces ofglass which reflect light. The mounting of such jewel-like elements instuds of rugged character is similarly so expensive as to be almostprohibitive for the provision of a highway marker of general utility.Moreover, adequate anchorage of such stud-like road-marking devices, asa class, is extremely diflicult and further increases the cost of thefinished highway line to such an extent that, as has been stated,painted lines, despite their short life, continue to be the expedientmost generally used.

Relatively recently, efiorts have been made to employ a, ribbon or stripof lustrous metal and to anchor the metallic strip by means of. anadhesive such as asphalturn. While such a construetion has great meritfrom the standpoint of enhanced visibility and facility and rapidity ofinstallation, the difliculty of obtaining an adhesive bond of adequatetenacity, especially on concrete highways, is self-apparent. Such aconstruction suffers damage not only by reason of the scraping andplucking action of vehicle wheels in lateral skidding and braking,especially when the wheels carry chains, but also by reason of theingress of water, oil and dirt beneath the strip. In concrete roadways,particularly, con- (till. tit-1L5) siderable moisture reaches such astrip, or its adhesive backing, through capillary attraction due toinherent porosity of such roadway materials as concrete. Diflerentialthermal expansion and contraction also eflects a buckling oi the stripduring extremes of temperature, with the result that the strip maybecome so wrinkled as to periodically lift from the surface of theroadway. Under such conditions, dirt will enter between the strip andthe underlying roadway surface at, numerous points, destroying theadhesive bond and assuring easy tearing and separation of the strip byvehicle wheels.

Other methods have been attempted, such as edgewise flanging of suchstrips into U term and the imbedding of the flanges in the material ofthe roadway. While the anchorage thus adorded is highly satisfactory,such structures are limited, for all practical purposes, to installationin new roadways during their construction. Such strips also areextremely expensive because at the highcost non-corrosive metalsrequired, as well as the dimculty of drawing and shaping the strips.Moreover, the application of such a structure to curves .(which,incidentally, are the most common locations requiring marking) ispractically impossible, except where the'strip is of preformed curvedconfiguration. Fabrication of such flanged strips in sections havingcurvatures of varying intensity involves manufacturing and shippingexpense which is substantially prohibitive. Glare resulting fromreflection of sunlight and light from approaching vehicle headlights, aswell as the hazard of skidding on such rolled metallic strips, arefurther complications which adversely affect their adoption.

With the foregoing prior art structures and attendant problems in mind,my invention has, for its purpose, several well-defined objects. Theprimary object of my invention is to provide a zone-defining road markerwhich is rugged and will successfully withstand the numerous stressesand strains to which such markers areinherently acteristic of sodiffusing light reflected from the additional traffic hazard.

It is an object of my invention to provide a low-cost traific markerwhich, like the painted line, is formed in situ upon the road surface.

It is an object of my invention to provide a trafilc marker which may beinstalled upon existing highways with facility equal to installationupon new highways.

It is an object of my invention to provide a traffic marker which, whenworn, as may occur after along period of severe use, may be renewed,

or built up, with facility equal to the renewal of the painted line.

It is an object of my invention to provide a traffic marker which,though low in cost of installation, is not subject to injury bycorrosion.

It is an object of my invention to provide a traflic marker which has asatisfactory coefficient of friction, and which, therefore, will notmaterially increase the road hazard known as skidding.

, It is an object of my invention to provide a road marker which isinherently bonded to the highway surface and which requires no adhesivebinding.

It is an object of my invention to provide a road marker which may beinstalled with such rapidity that no interference with the normal use ofthe highway is occasioned.

It is an object of my invention to provide a highway marker which may beinstalled with accurate uniformity and which will present a pleasingappearance to the eye.

Further objects and objects relating to details and economies ofconstruction and use will definitely appear from the detaileddescription following. In one instance, I accomplish the objects of myinvention by the means set'forth in the following specification. Myinvention is clearly defined in the appended claims. A structureconstituting a preferred embodiment of my invention is illustrated inthe accompanying drawing, in which:

Figure 1 is a perspective view of a section of highway provided with acentral longitudinal highway marker constituting a preferred embodimentof my invention;

Fig. 2 is a cross-sectional view of a portion of concrete highwayprovided with a highway marker of the form illustrated in Fig. 1;

Fig. 3 is a diagrammatic view of a portionof apparatus employed for theinstallation of a highway marker of the type illustrated in Figs. 1 and2, portions of said apparatus, as well as of the highway and marker,being shown in crosssection; and

Fig. 4 is a diagrammatic view of a preferred form of apparatus forforming the highway marker illustrated in Figs. 1 and 2.

Similar reference numerals refer to similar parts throughout the severalviews.

In general, my invention consists inthe provision of a narrow, band-likehighway marker consisting of a narrow, tape-like, lustrous,corrosionresistant strip of metal formed upon the surface of the highwayand mechanically bonded directly thereto by casting thereon in situ.

More particularly, and with reference to the accompanying drawing, inwhich I have illustrated a preferred embodiment of my invention, thereis shown a cast strip in of zinc of elliptical cross-section embedded,inlay fashion, in a complementary trough or channel ll, formed in thesurface of a conventional highway l2. Preferably, though not by way oflimitation, my inven- -headlamps of approaching vehicles as to offer notion has particular application to monolithic highways such as areconventionally formed of concrete and provided with periodic expansionJoints or gaps l3 suitably filled with resilient or compressiblematerial I4. In employing the term casting, particular reference is madeto that method of casting which is effected by the spraying of moltenmetal in atomized form, and in which the atomized particles are in anunstable physical condition characterized by temporary plasticity suchthat solidification occurs at, or directly after, the moment of theirdeposit upon the surface being sprayed.

This general method of casting by atomization and projection of moltenmetal is well-known and, for an understanding thereof, reference is madeto the patent of Donald D. Taylor, No. 1,934,891, granted November 14,1933, which patent discloses an apparatus of the general type adaptedfor the production of metal coatings generally. In Figs. 3 and 4, thereis diagrammatically illustrated apparatus including severalmetal-spraying nozzles I5 of the general type illustrated in the Taylorpatent aforesaid, assembled in staggered relation. About the nozzles I5is mounted a shield l6 consisting of side plates i1 and I8 inclinedtoward their lower edges to constitute a mask held in slightly spacedrelation with respect to the roadway surface by a suitable carriage (notshown). The carriage also supports .one or more sand-blasting nozzlesl9, which are directed to discharge sand upon a narrow, bandlike portionof the highway, directly in advance of the metal-spraying nozzles IS.The sandblasting nozzles are also preferably so inclined with respect tothe band-like portion of the roadway surface as to not only clean thesame of foreign matter, but also to provide a myriad of minute pits fora purpose later to be described. The shield member iii of the apparatus,in addition to the side plates I! and I8, is provided with a forwardplate 20, the lower edge of which is similarly maintained in closeproximity to the roadway surface. Mounted upon the plate 20, anddisposed intermediate said plate and the sand-blasting nozzles I9, is anair jet 2| arranged to discharge a broad jet of compressed air direct-1y forward of the plate 20 to constitute an air curtain as well as acleaner for removing such loose particles of sand as remain upon thebandlike, pitted surface of the roadway prior to the spraying thereofwith plastic metal discharged from the jets I5. Following the jets IS inclose proximity thereto, is a rotary wire brush 22 journaled in thecarriage (not shown) which supports the jets l5 and the shield l6.

More specifically, it will be noted that the staggered metal-sprayingnozzles l5 are inclined with respect to the vertical and are so directedupon the sand-blasted portion of the highway surface as to deposit thedensest portion of their respective streams of atomized metal along themedian zone thereof and thus build up a "crowned strip having a maximumthickness along its central portion. Moreover, the pro-. jection ofmetal upon the pitted, band-like surface at an angle, and from twosides, insures an interlocking of the strip as formed, with the myriadof pits and projections in the roadway surface. As a result, themetallic strip becomes, in effect, an integral portion of the highway,such that dislodgment therefrom, even under the most severe stresses, isa practical impossibility.

A metal strip, cast in the manner described, has the characteristic ofbeing rather crystalline in structure, as distinguished from a strip ofmetal which has been rolled or drawn. As a result, the appearance oi!the lustrous surface thereof, even when worn, is satin-like or slightlyrough,

rather than brilliant and dazzling. This is an metals are relativelyeasy to spray, having low melting pointsand requiring low fuelconsumption. They are amply light-reflective for the purpose,inexpensive, corrosion-resistant, and have good wearing properties.

Under some conditions, and in employing met-- ads which take a highpolish under the action oflight tramc, it has been found desirable todiagonally striate the strip after formation. a For this purpose, thewire brush ft is employed, which brush is diagonally journaled upon thesupporting carriage and driven by a motor (not shown) at a moderatespeed. Preferably, such striations it are formed transverse the strip itat an angle such that they are substantially perpendicular to light raysforwardly and downwardly proiected from approaching vehicle lamps. Thesestriations tend to break up or diffuse light otherwise refiected to theeyes of drivers traveling in the opposite direction.

With an apparatus of the type heretofore described, the rate at whichthe strip fill may be installed is limited and determined solely'by thedesired thickness of the strip.

The strip illustrated in Figs. 1 and 2 is of elliptical cross-sectionand great thickness. For most purposes, a strip of far less thicknesswill sulhce. Where a strip having a thickness of as little as .010 of aninch is employed, it is unenecessary to countersink the same as shown,although a cleaning and roughening of the highway surface is essentialto obtainadequate anchorage of the strip. With such interlocking ofstrip and roadway proper, diderential thermal expansion and contractionhas been found not to sheet localized buckling or breakage of the strip,apparently because'the stresses are uniformly distributed for the fulllength of the strip section.

Preferably, where the strip is applied to con crete highways, it shouldbe interrupted at the conventional expansion gaps or joints, as shown.

if am aware that the embodiment of my inven tion herein illustrated anddescribed is susceptible of considerable modification without depar turefrom the broad concept thereof. While zinc and aluminum have been foundadmirably well suited for the purpose of the present invention, othermetals, pure or alloyed, may be employed. dimilarly, changes in the sizeand form of the strip are optional expedients. Likewise, thoughillustrated as a two-lane dividing tramc marker, it is equallyapplicable to definition of crosswalks in municipal areas. These andother variations will readily appear to those familiar with the objectsand teachings of the present invention. f therefore claim my inventionbroadly, as indicated by the appended claims.

Wt f claim is:

l. h roadway having a roughened, band-like surface formed therein, and ametallic strip coextensive with said band-like surface, in directcontact with said band-like surface and integrally mechanically bondedthereto in interlocking relation therewith by casting.

, 2. A roadway having at roughened, narrow, band-like surface formedtherein, and a narrow metallic strip coextensive with said band-likesurface, in direct contact with said band-like surface and integrallymechanically bonded thereto in interlocking relation therewith byfusion.

lid

3. A roadway having a shallow, band-liketrough formed therein, the wallsof which trough are roughened, and a narrow metallic inlay of strip formset in said trough, in direct contact with the walls thereof andmechanically interlocked therewith by fusion.

4i. a concrete roadway having a narrow, bandlike, pitted surface formedthereon, and a narrow metallic strip coextensive with said bandlikesurface, said metallic strip having its lower face of a formcomplementary to said pitted surface and interlocked therewith bycasting of said strip in situ upon said pitted concrete surface,

5. fl roadway having lateral convexity or "crown", the apex of saidcrown being provided with a. narrow, band-like surface of roughenedcharacter coaxial with said road, and a narrow metallic stripcoextensivewitlr said band-like surface, said strip beingcomplementarily rougherred on its under surface and interlocked withsaid roughened surface by casting thereon in situ.

d. A roadway having a narrow, band-like, pitted surface formed thereon,and a narrow cast metallic strip coextensive with said band-likesurface, said metallic strip being of generally crescent cross-sectionand having its two faces tary to and interlocked with the pits of saidband like roadway surface.

h. ll roadway having a superficial trough formed therein, the walls ofwhich trough are provided with a myriad of minute pits andprotuberances, and a thin metallic inlay of a thickness greater thansaid trough, said inlay being formed therein in situ and having itsunder face in direct con tact with said trough walls and of a roughenedconfiguration complementary to and interlocked with said trough walls.

9. ll roadway having a roughened, narrow, band-like surface formedtherein, and a thin strip of due cast directly upon said band likesurface complementary thereto and mechanically interlocked therewith.

re. A roadway having a roughened, narrow, band-like surface formedtherein, and a thin strip of aluminum cast directly upon said band-,like surface complementary thereto and mechanicallyinterlocked'therewlth.

' ll. h roadway having a roughened, narrowband-like surface formedtherein, and a thin strip of corrosion-resistant metal cast directlyupon said band-like surface complementary thereto, having its under faceemaul u 1mm terlocked therewith, and having its exposed surface ofroughened, light-diffusing character.

12. A roadway having a roughened, narrow, band-like surface formedtherein, and a thin strip of corrosion-resistant metal cast directlyupon said band-like surface complementary thereto, having its under facemechanically interlccked therewith. and having its exposed surfaceirregularly striated to afford a non-glaring traction surface.

13. A roadway having a roughened, narrow. band-like surface formedtherein. and a thin strip of corrosion-resistant metal cast directlyupon said band-like surface complementary thereto, having its under.face mechanically interlocked therewith, and having its exposed surfacediagonally striated to afi'ord a non-glarin traction surface.'

14. A crowned roadway having a narrow, pitted, band-like surface formedtherein, and a thin strip of corrosion-resistant metal cast directlyupon said band-like surface complementary thereto, having its under facemechanically interlocked therewith, and having its upper face laterallycurved on a radius shorter than the radius of lateral curvature of theroad proper,

said differential curvature being such as to divergently reflect lightbeams projected axially of the roadway and insure continuity of thestrip even though narrowed by long, continued wear.

15. The method of defining a traffic lane upon the surface of a. highwaywhich consists in removing trafllc film from said surface along theboundary of the lane, roughening said surface along said boundary toprovide a myriad of minute pits and projections therein, and so castinga strip of non-corrosive metal in situ upon said clean, roughenedsurface as to effect mechanical interlocking of said strip upon saidboundary surface.

18. The method of defining a traffic lane upon the surface of a highwaywhich consists in removing trafilc film from said surface along the,boundary of the lane, roughening said surface along said boundary toprovide a. myriad of pits and projections therein, so casting a strip ofnoncorrosive metal in situ upon said clean, roughened surface as toeffect mechanical interlockin of said strip upon said boundary surface,and finally diagonally striating the exposed surface of said strip.

DONALD D. TAYLOR.

